The number two U.S. commander in Iraq says the counter-insurgency operation north of Samarra is continuing with virtually no resistance, and will go on until the area is clear of insurgents and their weapons caches. General Peter Chiarelli says the Iraqi forces that form the majority of troops in this operation are performing very well, and he believes Iraq's new army will take security control for 75 percent of the country by the end of the summer.

Speaking from Baghdad, General Chiarelli said on the second day of the offensive, known as Operation Swarmer, U.S. and Iraqi forces continued to sweep 250 square kilometers for insurgents and weapons caches. The general said the largely desert area is sparsely populated and is used by insurgents mainly to hide weapons and other material.

He said the operation will continue for several days.

"We're not going to leave until we've done everything we need to do out in that particular area of operations," he said.

General Chiarelli also says the size of the area was the reason this was the largest airborne assault operation since the early weeks of the war. That distinction resulted in a lot of media attention for the operation, which some officials believe exaggerated its importance. But the general denied speculation by some American analysts that the operation was timed to coincide with Thursday's announcement of President Bush's National Security Strategy, in an effort to increase public support for the war.

"There was no attempt on anybody's part back here to time this to anything other than the intelligence that was coming in," he added. "It was an operation that we had been working for a couple of months."

The spokesman for the 101st Airborne Division, which is conducting Operation Swarmer with the Iraqi units, says a total of about 50 people have been detained, most of them on Thursday, and 17 have already been released. Speaking from the Division's headquarters in Tikrit, Lieutenant Colonel Ed Loomis told VOA no more weapons caches have been discovered beyond the six found on Thursday. But he says it is important to continue searching the area.

"A methodical search of this area near Samarra is important to do because, just because we had initial success with the opening hours of the operation doesn't mean we should rest on our laurels," said Loomis. "We need to give the area a good going over, searching with our Iraqi partners, to make sure there's no detectable capacity of insurgents to base from this area."

Lieutenant Colonel Loomis also says the operation has faced no resistance, and resulted in no casualties among military forces or civilians. He says once this operation ends, security in the remote area will be monitored from bases near Samarra and other nearby towns.

General Chiarelli said one noteworthy aspect of Operation Swarmer was the increased role of Iraqi forces. He said the Iraqi army is progressing well, and should be able to take control of the vast majority of Iraqi territory by August.

"By this summer, about 75 percent of Iraq, that battle space will be owned by Iraqi units," he noted. "We're finding Iraqi units, with our support, can be used in just about any operation we do in a counter-insurgency role. This is a force we have built, and the Iraqis have built, for that counter-insurgency fight. And I think they're particularly well-prepared, well-trained, and have the ability to do that in just about any area."

The general said Iraqi forces now control less than half of the country. Still, officials point out that most of the insurgent and sectarian violence in Iraq is limited to just a few provinces, while the rest of the country is relatively peaceful. They also note that Iraqi forces will continue to rely on U.S. and coalition forces for air support, logistics, intelligence and other functions. And General Chiarelli noted that the Iraqi national police, who will have responsibility for keeping order in local areas, are about a year behind the army in their development.

Officials say the progress of the Iraqi police and the army, the strength of the insurgency and the ability of Iraqi politicians to form an inclusive, competent government will be key factors in a decision expected within the next few months on whether there will be a further reduction in U.S. troop levels.